There are vanes on the market designed to clamp to the forestay. With the N6.0, however, the bridle rides ahead of the tack and doesn't allow anything to be mounted to the stay.



You may be able to mount it on the post. As for drilling the foil, the adapter I have on mine is mounted near the leading edge of the foil with two rivets.



While I'm no engineer, I don't see the mount as creating a stress point any more than the mount for the striker post. (Mine's been in place for six years.)